How do you mount one of these things on the centre console dash, and what guages are most useful to display if you leave it on?

It comes with a mount that uses double sided tape. Mine kept falling so I replaced the double sided tape with some 3m heavy duty hook and loop fastening system (a.k.a. Velcro but not the soft fuzzy kind. More of a hard plastic kind).

I like to keep my gauges set to monitor boost, Dam, fine knock learning, and feedback knock correction. Knock is crucial to your engine health and should always be monitored when available.